If you’ve ever felt that mass-produced wines are starting to taste increasingly similar, you may be on to something. A new report by the University of Adelaide has found that global wine growing has tilted to a select few grapes over the past decades, with Cabernet Sauvignon leading the pack.

Since 1990, Cab Sav and Merlot have doubled their share of hectares under production, making them the top cultivated varieties in the world. The Spanish varietal Airén has slipped into third place from the top spot it once enjoyed, while Tempranillo and Chardonnay have more than trebled their areas of cultivation to move into fourth and fifth place.

Once widely produced varieties, such as Georgia’s Rkatsiteli and the Turkish Sultaniye — formerly the world’s second and third most grown varieties — have all but vanished from the scene.